In recent years there has been a tremendous growth in the use of protective, safety and sports eyewear. Examples are ski goggles and safety glasses worn in industrial settings. The lens portion of the goggles receives the greatest amount of wear and damage and they regularly become scratched and broken. This often occurs in sporting applications where the user falls while wearing the goggles or when the lens becomes scratched or cracked, therefore needing replacement. For various reasons, it is economically desirable to replace the lens portion of the eyewear when needed rather than replacing the entire article. There are also applications in which the lens needs to be interchanged with a different type of lens given a change of circumstance or environment. For example, different types of tinted lenses are used by skiiers given different ambient lighting conditions such as sunny versus cloudy days.
Most commercially available goggles which provide the functionality of lens interchangeability utilize a flexible elastomeric ring which encircles the lens. To remove the lens, it must be pried from a groove in the surrounding ring. This is a difficult and time-consuming procedure which is hard to perform without a tool other than one's fingers. This can be even more frustrating when the lens removal and replacement needs to be accomplished outdoors where tools are not available.
There have been attempts disclosed in the patent art to provide goggles with interchangeable lenses to satisfy this need. Examples include U.S. Pat. No. 5,815,235 issued to Runckel entitled “Ski Goggles with Pivotal Frame Members for Interchanging Lenses.” This patent discloses a pivoting lower frame member which opens the encasement of a single lens that then may be easily extracted and replaced. The problem with this design, however, is that the lens is not sufficiently supported, and firm capture of the lens within the frame members is dependent upon excessive compression from the frame elements which often loosen, leading to a loss of sufficient grip on the lens.
Another attempt at providing sports eyewear with an interchangeable lens is the safety eyeglasses disclosed in U.S. Pat. No. 7,011,404 issued to Howard et al. entitled “Safety Glasses with Pivoting Interchangeable Single-Lens.” This document discloses a substantially rigid frame with a snap-in lens which pivots into and out of a locked position. In addition, a nose bridge portion or the center of the browbar may include a locking mechanism for holding the lens in position. While such eyewear provides an easily interchangeable lens, it does not provide adequate eye protection or stability required of sports ski goggles.
There is therefore a need in the art for goggles which include a lens that is easily interchangeable. There is a further need for goggles with an interchangeable lens system that does not require additional tools. And finally, there is a need in the art for goggles with an easily interchangeable lens system which is durable and economical to manufacture.